Optimizing: Tag arena allocations in code generators.

And completely remove the deprecated GrowableArray.

Replace GrowableArray with ArenaVector in code generators
and related classes and tag arena allocations.

Label arrays use direct allocations from ArenaAllocator
because Label is non-copyable and non-movable and as such
cannot be really held in a container. The GrowableArray
never actually constructed them, instead relying on the
zero-initialized storage from the arena allocator to be
correct. We now actually construct the labels.

Also avoid StackMapStream::ComputeDexRegisterMapSize() being
passed null references, even though unused.

Change-Id: I26a46fdd406b23a3969300a67739d55528df8bf4
diff --git a/compiler/optimizing/parallel_move_test.cc b/compiler/optimizing/parallel_move_test.cc
index f8f7010..da91cb8 100644
--- a/compiler/optimizing/parallel_move_test.cc
+++ b/compiler/optimizing/parallel_move_test.cc
@@ -56,7 +56,8 @@
       : ParallelMoveResolverWithSwap(allocator) {}
 
   void EmitMove(size_t index) OVERRIDE {
-    MoveOperands* move = moves_.Get(index);
+    DCHECK_LT(index, moves_.size());
+    MoveOperands* move = moves_[index];
     if (!message_.str().empty()) {
       message_ << " ";
     }
@@ -68,7 +69,8 @@
   }
 
   void EmitSwap(size_t index) OVERRIDE {
-    MoveOperands* move = moves_.Get(index);
+    DCHECK_LT(index, moves_.size());
+    MoveOperands* move = moves_[index];
     if (!message_.str().empty()) {
       message_ << " ";
     }
@@ -127,7 +129,8 @@
   void FreeScratchLocation(Location loc ATTRIBUTE_UNUSED) OVERRIDE {}
 
   void EmitMove(size_t index) OVERRIDE {
-    MoveOperands* move = moves_.Get(index);
+    DCHECK_LT(index, moves_.size());
+    MoveOperands* move = moves_[index];
     if (!message_.str().empty()) {
       message_ << " ";
     }